Foldable traverse curtain and construction units therefor



March 28, 1961 JAMES HlRASHlKl 2,976,923

FOLDABLE TRAVERSE CURTAIN AND CONSTRUCTION UNITS THEREFOR Filed Sept. 25, 1958 5 Sheets-Sheet 1.

60 /;/1f/27 60/ -52 55- 3-a .HHHHuh, .IHYTF M4 HI MW" 56 WW 5% 55- -52 54- i -35- INVENTOR. JAMES H l RASHIK! 2 ATTORNE March 28, 1961 JAMES HlRASHlKl FOLDABLE-TRAVERSE CURTAIN AND CONSTRUCTION UNITS THEREFOR Filed Sept. 25, 1958 5 Sheets-Sheet 2 IN VEN TOR. JAMES HIRASHIKl Wm W March 1961 FOLDABLE TRAVERSE CURTAIN AND CONSTRUCTION UNITS THEREFOR Filed Sept. 25, 1958 5 Sheet -s 3 HUMTM INVENTO ATT RNE March 28, 1961 JAMES HlRASHlKl 2,976,923

FOLDABLE TRAVERSE CURTAIN AND CONSTRUCTION UNITS THEREFOR Filed Sept. 25, 1958 5 Sheets-Sheet 4 INVENTOK JAMES HIRAS AT RNE 5 March 28, 1961 JAMES HlRAsHlKl 2,976,923

FOLDABLE TRAVERSE CURTAIN AND CONSTRUCTION UNITS THEREFOR Filed Sept. 25, 1958 5 Sheets-Sheet 5 \fi? A o 25 2|e 20e- -2o5 INVENTOR. JAMES HIRASHIKI A TTORNE V5 United States Patent C FOLDABLE TRAVERSE CURTAIN AND CON- STRUCTION UNITS THEREFOR James Hirashiki, 2629 S. Halldale Ave., Los Angeles 18, Calif.

Filed Sept. 25, 1958, Ser. No. 763,321

19 Claims. (Cl. 160-229) The present invention is directed generally to the provision of a foldable traverse curtain or screen structure and to component blocks or units of which such a structure may be made.

This application is a continuation-in-part of application Serial No. 541,928, filed October 21, 1955, now abandoned.

In the blocks of the present invention there is provided a body of generally rigid material defined laterally by spaced parallel rectangular end strips disposed in veritcal orientation and of appreciable depth. Web means having web portions extend between and are by preference formed integrally with the end strips, portions of the web means lying in planes in substantial alignment with the front and the rear edges of the end strips. Means are provided for joining a plurality of the blocks in interengaging relation to form a screen structure. Such means desirably include hinge elements preferably formed integrally with the blocks proper, each hinge element desirably taking the form of a knuckle barrel having a vertically disposed bore formed therein, the bore lying substantially in the plane containing either the front or the.

rear edge of the end strips, the planes containing the bores being thus spaced by the thickness of the blocks. Each of the knuckle barrels extends no more than onehalf the height of the body, and each block has two such barrels so arranged that a suspension rod may be pivotally received in the bores of two horizontally adjacent blocks to hingedly connect them. Such suspension rods may be passed through the bores'of a number of blocks in vertical alignment to form pivotally connected panels constituting a traversable curtain structure. The web portions of the blocks may be configured in a number of different ways to provide various functional and decorative effects, the preferred form including web portions so disposed as to provide openings from one face of .the body to the other so that the completed curtain or screen structure permits ventilation. Desirably these openings are formed and arranged to minimize or virtually prevent light passage therethrough in a direction normal to the general plane of the block. Thus when the block body is made of non-transparent material, the arrangement of the openings is such that virtually complete visual privacy results.

Accordingly, it is a principal object of the present invention to provide novel improvements in traversable curtain construction and component blocks used therein.

Another object of the invention is to disclose a movable screen structure made up of articulated component blocks which may be easily and economically manufactured in quantity of suitable plastic material.

A further object is to provide a movable screen structure of the above character providing a number of ventilating openings therethrough so arranged that the screen as a whole provides virtually complete visual privacy.

These and additional objects and purposes of the invention will he understood by a study of the following description of preferred embodiments of the invention ice " taken in connection with the accompanying drawings, in

26 in a first vertical column or panel A and blocks inwhich Fig. 1 is a fragmentary side elevational view of a lower corner portion of a curtain or screen structure in acoutline, a fragmentary portion of a vertically adjacent block in the common vertical panel. 7

Fig. 3 is a fragmentary top plan view of a portion of atypical rail structure from which portions of a screen in accordance with the present invention are suspended, a portion of the rail being broken away for clarity of illustration.

Fig. 4 is a fragmentary exploded view of a preferred form of the articulated joint between adjacent top cross pieces or headers in accordance with the invention.

Figs. 4a and 4-b are fragmentary sectional views showing the operation of the articulated joint of Fig. 4.

Fig. 5 is a fragmentary sectional view taken on the line VV of Fig. 3. i

Fig. 6 is a perspective view of an alternative form of the component block in accordance with the present invention.

Fig. 7 is a fragmentary view in perspective of a screen 7 Fig. 9 is a perspective view of another modified form of the screen or curtain structure of the present invention.

Fig. 10 is a perspective view of a component block used in the structure of Fig. 9, a part being broken away for clarity of illustration.

Fig. 11 is a. perspective view of a portion of a screen or curtain structure embodying another modified form of the invention, a part being broken away for clarity of illustration. I

Figs. 12 and 13 are perspective views of component blocks used in the structure of Fig. 11, a part in Fig. 12 being broken away for clarity of illustration.

Fig. 14 is a fragmentary view of another modified form of screen or curtain in accordance with the present invention, a part being broken away for clarity of illustration.

Figs. 15 and 16 are perspective views of component blocks used in the structure of Fig. 14.

Referring now in detail to the drawings, the lowermost portion of a screen or curtain structure appearing in Fig. 1 includes block units indicated generally at 25 and includes diagonally opposed rectangular web means having portions 32 and 33 lying in the plane of the front edges of the end strips 30 and 31 as well as diagonally opposed rectangular web portions 34 and 35 lying in the plane containing the rear edges of the end strips 30 and 31. The web portions 32, 33, 34 and 35 are desirably of equal thickness, such thickness being substantially less than the depth of the end strips '30 and 31. The web portion 33 terminates upwardly in an upper edge 40 and web portion 34 terminates in a lower edge 41, the edges being horizontally aligned and spaced apart to define between them a horizontal ventilating opening 42. The

Patented Mar. 28, 1961 horizontally adjacent web portions 32 and 34 are joined together by a central strip 43 extending the entire height of the block, the central strip being parallel to and desirably equidistantly spaced between the vertical end strips 30 and 31. The lower portion of the central strip 43 serves to extend between and join the horizontally adacent web portion 33 and recessed web portion 35. An opening 46 corresponding to the opening 42 is formed between the lower edge 47 of the web portion 32 and the upper edge 48 of the web portion 35.

Hinge means are provided on the block 25 and are here shown as including a tubular knuckle barrel 52 having a vertical bore 53 therethrough and knuckle barrel 56 having a vertical bore 57 therethrough, the axis of the bore 53 lying in the frontal plane defined by the front edges of the end strips 30 and 31 and the bore 57 having its axis in the rear plane defined by the rear edges of the end strips 30 and 31. The hinge barrels 52 and 56 extend no more than one-half the overall height of the end strips 30 and 31 and, when the block 25 is formed of cast or molded plastic material, the hinge barrels as well as the other components of the block are desirably formed integrally. It will be noted that the hinge barrels 52 and 56 are mutually offset in two senses, both vertically and in depth normal to the block, the barrels being thus disposed symmetrically about the center point of the block.

In the assembly of a number of the blocks into the curtain or screen structure fragmentarily shown in Fig. 1, the blocks in the column A are all similarly oriented. Thus the knuckle barrel 52 of the block 26 is disposed so that the bore formed therein is aligned with the bore 53 of the knuckle barrel 52 of the vertically adjacent block 25 and a suspension rod 60, desirably made of metal, passes through such aligned bores. The upper end of the suspension rod 60 is suitably supported as will be described later and the lower end is desirably provided with an enlarged portion 61 in abutment with the lower face of the knuckle barrel 52 to support the latter. For purposes of appearance when the column A is an end column in an installation as is assumed in Fig. 1, there is desirably provided a separate tubular spacer member 62 of the same size and appearance as one of the knuckle barrels 52 and 56, the spacer 62 including a bore 63 for receiving the suspension rod 60. It is to be noted that, as appears in Fig. 2, a web portion in the lower block, corresponding to the web portion 34 in the upper block, is adjacent to the web portion 33, and that such web portions are in spaced planes. In the same manner, a web portion in the lower block corresponding to the web portion 32 in the upper block is adjacent to the web portion 35 and that such Web portions are also in spaced planes. The bottom edges of the web portions 33 and 35 are aligned with the top edges of the adjacent web portions in the lower block, and thereby additional ventilating openings 65 are formed between vertically adjacent blocks when assembled, supplementing the openings 42 and 46 within an individual block.

The individual component blocks in the adjacent column B, such as blocks 27 and 28, are reversed in orientation relative to the position assumed in column A. Thus if the block 25 as seen in Fig. 2 is rotated 180 about an axis perpendicular to the general plane of the block and centrally thereof, it will assume the position of blocks 27 or 28. Under these conditions the knuckle barrel 56 of the block 27 will be brought into vertical alignment with the knuckle barrel 56 of the block 25. The suspension rod 60 passes through the barrels as thus aligned, terminating downwardly in an enlarged head 61 serving to support a lowermost block 23 by abutting contact with the lower face of knuckle barrel 56. It will be readily understood that the blocks in column C are oriented like those in column A.

The structure of the present invention is suspended as 'tially fully extended position.

from a ceiling or the like by a suitable traverse means such as are indicated in Figs. 3, 4 and 5. As there shown, the traverse means includes a rail indicated generally at 70 and best seen in Fig. 5, having an upper fiat portion 71 and downwardly extending side Walls 73 and 74 terminating in inturned portions 75 and 76, the latter portions forming an open slot 77 giving access from below to the hollow channel 78 within the rail 70. Rollable support means indicated generally at 80 are housed within the channel 78 and include a pair of spaced rollers 81 and 82 rollably engaging the inturned fiat portions 75 and 76. The rollers are connected by a support shaft 33 which passes through an enlarged central hub member 84 in which the upper enlarged end 85 of a connector bar or rod 86 is received, the lower portion of the bar being embedded in a cross piece or header indicated generally at 90 and the parts being retained in assembled relation by an enlargement 85 at the lower end of the bar 86.

The cross piece or header 90 is a generally rectangular member having a horizontal length equal to the width of one of the component blocks such as block 25. As best appears in Fig. 4, the header 90 is provided with suitable hinge means for articulately connecting with a similar header a portion of which is indicated generally at 91. In the present illustration, the hinge means include a knuckle barrel '92 connected to the outer edge of the header 90 and provided with a vertical bore 93 extending therethrough. The other header 91 includes a knuckle barrel 94 similarly provided with a vertical bore 95 extending therethrough. Stop means are provided for limiting the angular swinging of one of the headers 90 relative to the adjacent header 91 and such stop means are here shown as including a downwardly projecting lug 96 carried by the barrel 92 and having a face or shoulder 97 and an upwardly projecting lug 98 carried by the barrel 94 and provided with a face or shoulder 99. It Will be seen that when the parts are assembled with one of the suspension rods 60 passing through the bores 93 and 95, the faces 97 and 99 may be angularly spaced apart as appears in Figure 4a, or the parts can be pivotally swung about the axis of rod 60 so the faces are brought into abutment as indicated in Fig. 4b, thereby preventing further clockwise movement of the support arm 90' about the axis of the rod 60. It will be understood that the provision of the angular travel stop means such as the abutment faces 97 and 99 may not in all installations be necessary, although smooth operation of the curtain is generally facilitated when the component articulated panels of the screen are prevented as by the stop means described from occupying a common plane. Accordingly, the portions of the panels A, B, C and D indicated in Fig. 3 illustrate the somewhat zig zag position which the panels take when in substan- It may also be noted in Fig. 3 that a support carrier 80 described in connection with Fig. 5 need not necessarily be used in connection with every one of the panels. Normally, every alternate panel is suflicient and this arrangement is desirable in permitting the movement of the curtain into very compact position when desired.

In Fig. 6 there is illustrated a modified form of block indicated generally at 100 for use in the present invention. In the block 100 the end strips 101 and 102 are in spaced parallel relation and are vertically oriented, each of the end strips having integrally fixed thereto a knuckle barrel 103 and 104 respectively. As in the form of the invention described in connection with Fig. 2, the knuckle barrels 103 and 104 are displaced on opposite sides of the medial vertical plane extending centrally of the depth of the end strips 101 and 102 so that the axes of the respective barrels lie in the rear and frontal planes of the block respectively as determined by the rear and frontal edges of the end strips 101 and 102. The block 100 includes web means comprising an upper web portion 108 and a lower web portion 109, each portion being relatively thin as compared to the depth of the end strips 101 and 102 so that a ventilating opening 110 is formed between them and is defined by the lower edge 111 of the upper web portion 108 and the upper edge 112 of the lower web portion 109. Desirably these edges 111 and 112 are horizontally aligned so that substantial visual privacy is provided as in the case of the block of Fig. 2.

In the form of the invention shown in Fig. 7 including component blocks as seen in detail in Fig. 8, one such block as indicated generally at 120. This block includes vertically oriented spaced parallel end strips 121 and 122 and tubular knuckle barrels 123 and 124 fixed to the outer surfaces of the respective end strips, the cylindrical bores 125 and 126 of the barrels lying in the rear and frontal planes defined by the rear and frontal edges of the end strips 121 and 122 respectively. In this form of the invention there are provided web means having diagonally opposed web portions 130 and 131 lying generally in the frontal plane of the block and recessed web portions 132 and 133 also diagonally opposed and lying in the rear plane thereof. A central vertically extending strip 135 serves to separate the upper horizontally adjacent web portions 131 and 132 as well as the lower horizontally adjacent web portions 130 and 133. The vertically adjacent web portions 130 and 132 are joined by a curvilinear portion 136, while the vertically adjacent web portions 131 and 133 are joined by curvilinear portion 137. It is to be noted in this form of the invention that no openings are provided within an individual block, but such openings do result from the assembling of these blocks into a vertically extending panel. Thus, in Fig. 7, opening 140 is formed between verticallyadjacent blocks in the right half of the blocks while a similarly shaped opening 141 is formed in the left of the individual blocks.

In Figs. 9 and there is shown another modified form of the invention similar in certain respects to the preferred form of blocks as shown and described in connection with Figs. 1 and 2. Thus the block indicated generally at 150 is bounded laterally by the end strips 151 and 152, tubular knuckle barrels 153 and 154 being desirably formed integrally with the respective end strips and fixed to their outer faces, the knuckle barrels being symmetrically disposed about the center point of the block as in the case of block 25 of Fig. 2. The body portion of the block 150 includes web means having portions 156 and 157 lying generally in the frontal plane determined by the front edges of the end strips 151 and 152 as well as web portions 158 and 159 lying generally in the rear plane determined by the rear edges of the end strips. The horizontally adjacent web portions such as 156 and 158 are joined by a curvilinear junction 160, while the horizontally adjacent web portions 157 and 159 are joined by an oppositely curved curvilinear portion 161. Thus there are provided openings between the vertically adjacent web portions, such openings being here indicated at 162 between the web portions 157 and 158 and at 163 between the vertically adjacent web portions 156 and 159. It will be noted that these openings correspond to the openings =42 and 48 of the block shown in Fig. 2. The assembled screen structure of Fig. 9 contemplates the same arrangement with suspension rods 60 received in the bores of the knuckle barrels 153 and 154, in order to permit folding articulation of the screen.

In Figs. ll, 12 and 13 there is shown a further modified form of the present invention. The block shown in Fig. 12 and indicated generally at 170 includes spaced vertical end strips 171 and 172 having fixed thereto tubular knuckle barrels 173 and 174 respectively. The block 12 further includes web means having an upper web portion 175 and a lower web portion 176, these two web portions "being disposed in spaced paraller relation 0 and being inclined angularly to the general plane of the block 170. The lower edge 173 of the upper web portion 175 is spaced from and desirably is in substantial horizotnal alignment with the upper edge 179 of the lower web portion 176 thereby providing a ventilating opening 180 between the two web portions extending the entire width of the block between the inner faces of the end strips 171 and 172. In order to provide a completely assembled screen structure wherein all of the inclined web portions are inclined in the same general direction when the curtain is in extended position as seen in Fig.

11, there is provided a mating component block indicated generally at 182 in Fig. 13. Block 182 includes spaced parallel end strips 183 and 184 having fixed thereto tubular knuckle barrels 185 and 186 and web portions 187 and 108 extending between the end strips 183 and 184. The blocks are assembled to form the structure of Fig. 11 with the column or panel A of Fig. 11 including blocks 170, while the adjacent column or panel B includes blocks 182. Thus the successive vertical columns or panels are made up of the two similar but different styles of blocks in alternating relation. In addition to the ventilating opening formed between the Web portions of an individual block, an additional ventilating opening is formed between the upper web portion of one block and the lower web portion of the block immediately above. Thus in Fig. 11, the block is mounted beneath an identical block indicated generally at 190. It is to be noted that the lower edge 191 of the lower web portion 176 of the block 190 is in horizontal alignment with the upper edge 192 of the upper web portion of the block 170, thereby forming a generally rectangular ventilating opening 193 extending the width of the blocks. As pointed out previously, visual privacy is aiforded since light normal to the plane of the block cannot pass through the opening 103.

A further modified form of the invention is shown in Figs. 14, 15 and 16. The component blocks in this form of the invention are seen in Figs. 15 and 16 and are indicated respectively at 200 and 210. The block 200 includes spaced parallel end strips 201 and 202 having fixed thereto tubular knuckle barre-ls 203 and 204 respectively. The body of the block 200 includes web means'having a pair of web portions 205 and 206 lying respectively in the rear plane defined by the rear edges of'tlie end strips 201 and 202 and in the frontal plane defined by the front edges of the end strips. The web portions 205 and 206 are joined substantially centrally of the width of the block by a centralstrip 207 desirably parallel to strips 201 and 202. In the mating block 210 there are provided end strips 211 and 212 having fixed thereto tubular knuckle barrels 213 and 214 respectively. The block 210 further includes web portions 215 and 216 lying respectively in the rear and frontal planes defined by the edges of the strips 211 and 212, the web portions being joined substantially centrally of the block by a central strip 217 desirably parallel to strips 211 and 212. in the assembly of a complete screen or curtain in accordance with this form of the invention as appears in Fig. 14, the blocks are desirably arranged to provide ventilating openings between vertically adjacent blocks. Thus block 200 is assembled immediately above .one of the blocks 210, the latter block having been rotated from its position of Fig. 16 about an axis perpendicular to the general plane of the block to assume its position seen in Fig. 14. In this 'arrmgement the lower edge of the web portion 205 and the upper edge of Web portion 216 are in horizontally aligned spaced relation and define therebetween a ventilating opening 221. Similarly, the lower edge of the web portion 206 and the upper edge of the web portion 215 are in horizontally aligned spaced relation and define therebetween a ventilating opening 222. Horizontally adjacent blocks are desirably not of identical type but rather of mating type in order to preserve the alternating character of the frontal and rear web portions across the surface of the curtain. Thus in Fig. 14 block 2% in column or panel A is horizontally adjacent and in articulated relation with -a block 210 in column or panel B and in a third column C the upper block in the showing of Fig. 14 is again the block 2% as shown in Fig. 15.

The present construction wherein each vertical panel is made up of a plurality of individual component blocks is particularly advantageous as compared with an integral panel when rigid plastic material such as Tenite, butyrate, Lucite or Styron is used for the panel material. For example, consider a curtain made or" a number of integral panels each of the order of six feet or more long and three to six inches wide. In use such a curtain is exposed to sunlight, cooling air and other environmental factors. Frequently such exposure is not uniform throughout the length of the panel. As a result of this and of warping incident to aging and general wear and tear, elongated panels may become so distorted and deformed as to not only present an objectionable appearance but, more importantly, to malfunction mechanically Where any sort of articulation of similar movement of the complete screen structure is involved. However, where component blocks are assembled into a plurality of movable panels in accordance with the present invention,

the foregoing disadvantages are avoided since no conceivable amount of deformation of an individual block during use can result in malfunctioning such as binding on the vertical suspension rods constituting the pivotal axes connecting blocks of adjacent panels. The blocks of the present invention are contemplated to be rectangular or substantially so, with the height and width generally of the same order of magnitude, typically such dimensions being of the order of a few inches and only in unusual installations being a foot or thereabouts.

The blocks are formed to be thin relative to their height and width. Thus in a typical construction where the blocks may be, illustratively, approximately three inches square, their thickness, i.e. the depth or width of the end strips, may be of the order of one-quarter inch, the height and width thus being ten or more times the blocks thickness. When the web thickness is about one-sixteenth inch, as is desirable, the openings in blocks such as those of Figs. 1 and 2 will accordingly have a smaller dimension of about one-eighth inch. Thus the webs of a block are spaced apart by a distance somewhat less than the depth of the end strips.

I It is characteristic of the blocks that the tubular knuckle barrels are disposed in symmetry relative to the block center point so that the barrels of a block are displaced from one another vertically and their bore axes are displaced from one another in depth perpendicular to the general plane of the block. Preferably each barrel bore axis is aligned with one vertical edge of a strip, the other edge of the strip being unobstructed.

Modifications and changes not departing from the spirit of the invention are intended to be embraced within the scope of the appended claims.

I claim:

1. Block means for use in a traversable curtain made up of a series of articulated panels with each panel being made up of a series of similar stacked blocks, said block means comprising: a structure having a pair of laterally spaced, parallel, end strips, rigid web means carried by and extending between said end strips, said web means having adjacent portions lying in different planes, said adjacent web portions having a top edge and a bottom edge, the top edge of said one web portion and the bottom edge of the said adjacent web portion being spaced in a substantially horizontal direction whereby ventilating air passages are provided and direct light transmission is minimized through the block means; and hinge means attached to each of said end strips, the axis of the hinge means attached to one end strip being disposed forward of a median vertical plane of the block means, and the axis of the hinge means attached to the other end strip being disposed rearward of such median plane.

. 2. The invention as stated in claim 1 wherein said web portions are in parallel planes inclined to the vertical.

3. The invention asstated in claim 1 wherein said end strips are rectangular in form, vertically extending, and have a depth substantially greater than the web thickness, one web portion lying generally in a frontal plane defined by Vertical front edges of the end strips and another web portion lying generally in a rear plane defined by vertical rear edges of the end strips.

4. The invention as stated in claim 3 wherein each said web portion extends vertically the height of the block means.

5. The invention as stated in claim 3 wherein. each said web portion extends horizontally the width of the block means.

6. The invention as stated in claim 3 wherein each block means includes vertically adjacent web portions joined by curvilinearly shaped junction portions.

7. The invention as stated in claim 3 wherein each block means includes horizontally adjacent web portions joined by curvilinearly shaped junction portions.

8. The invention as stated in claim 3 wherein each block means includes a third vertical strip parallel to and disposed between said end strips and each block means includes vertically adjacent web portions having hori Zontally aligned edges defining a ventilating opening therebetween.

9. The invention as stated in claim 1, including a third strip intermediate and parallel with said end strips, said third strip extending the height of the block means, the edges of said strips defining a pair of vertical parallel planes spaced by substantially the depth of said strips, said Web portions extending between and formed integrally with the edges of the strips, said portions being spaced apart somewhat less than the strip width, there being at least two vertically adjacent potrions having edges aligned and in spaced relation defining an opening there'oetween.

10. The invention as stated in claim 1, in which each end strip includes frontal and rear vertical edges defining frontal and rear planes and in which said web means interconnecting said strips are formed integrally there with, said web means being substantially thinner than the block means thickness and including at least two generally flat portions lying in spaced parallel planes.

11. The invention as stated in claim 1 in which said hinge means for interconnecting with other block means comprises tubular knuckle barrels fixed to the outer surfaces of the strips and formed integrally therewith, the barrels being diagonally disposed on the block means, one barrel being fixed to the upper end of one strip and the other barrel being fixed to the lower end of the other strip, the barrels having vertical bore axes in the frontal and rear planes.

12. The invention as stated in claim 1, in which the top edges of the web portions defining the upper edge of the web means in the block means, and in which the bottom edges of the web portions defining the lower edge of the web means in the block means, are in alignment with the bottom edges and upper edges, respectively, of adjacent block means when stacked in a panel, and in which said adjacent edges are laterally offset, whereby ventilating air passages are provided and direct light transmission is minimized between adjacent block means.

13. Block means for use in a traversable curtain made up of a series of articulated panels with each panel being made up of a series of similar stacked blocks, said block means comprising: a structure having a pair of laterally spaced, parallel, end strips extending substantially the full height of the block means; rigid web means carried by and between said end strips and extending the full height of said end strips, said web means having a plurality of adjacent web portions, some of said portions being interconnected and offset relative to a median vertical plane of the block means, said adjacent web portions having a top edge and a bottom edge, the plane of one web portion being spaced laterally from the plane of an adjacent web portion and the top edge of said one web portion and the bottom edge of the said adjacent web portion being spaced in a substantially horizontal direction whereby ventilating air passages are provided and direct light transmission is minimized through the block means; and hinge means attached to each of said end strips and extending not over one-half the length thereof, the axis of the hinge means attached to one end strip being disposed forward of a median vertical plane of the block and the axis of the hinge means attached to the other end stn'p being disposed rearward of such median plane.

14. The invention as stated in claim 13 wherein said 15 web portions are arranged in parallel planes.

15. The inventionas stated in claim 13 wherein the block means includes a plurality of similar blocks and wherein each said web portion extends vertically the height of one of said blocks.

16. The invention as stated in claim 13 wherein each said web portion extends horizontally the width of the block means.

17. The invention as stated in claim 13 wherein each block means includes vertically adjacent web portions joined by curvilinearly shaped junction portions.

18. The invention as stated in claim 13 wherein each block means includes horizontally adjacent web portions joined by curvilinearly shaped junction portions.

19. The invention as stated in claim 13 wherein each block means includes a third vertical strip parallel to and disposed between said end strips and wherein adjacent vertical web portions are oifset and have horizontally aligned edges defining said air passages.

References Cited in the file of this patent UNITED STATES PATENTS 312,585 Seton et al. Feb. 17, 1885 1,613,047 Miller Jan. 4, 1927 2,351,656 Auten June 20, 1944 2,703,140 Bonawit Mar. 1, 1955 2,830,660 De Borger Apr. 15, 1958 FOREIGN PATENTS 16,540/28 Australia Apr. 17, 1929 

